1. 直接写出得数。
$60.51 - 0.51 =$ $0×1.87 =$ $2.09÷10 =$
$12.5 - 2.5 =$ $0.47 + 0.9 =$ $0.07 + 0 =$
$0÷241 =$ $5^{2} =$ $7.23 - 1.34 =$
$3.2 + 1.4 =$ $3.7 + 1.3 =$ $0.07 + 0.7 =$
$8 - 0.3 =$ $5.6 + 0.7 =$ $0.73 - 0.4 =$
$1 - 0.01 =$ $2.6 + 4 =$ $0.85 - 0.5 =$

60.51 - 0.51 = 60 0×1.87 = 0 2.09÷10 = 0.209
12.5 - 2.5 = 10 0.47 + 0.9 = 1.37 0.07 + 0 = 0.07
0÷241 = 0 5² = 25 7.23 - 1.34 = 5.89
3.2 + 1.4 = 4.6 3.7 + 1.3 = 5 0.07 + 0.7 = 0.77
8 - 0.3 = 7.7 5.6 + 0.7 = 6.3 0.73 - 0.4 = 0.33
1 - 0.01 = 0.99 2.6 + 4 = 6.6 0.85 - 0.5 = 0.35

2. 计算下列各题，能简算的要简算。
$3.26 + 5.9 + 6.74$ $50×0.39×0.4$ $2.8×102$
$0.125×73×80$ $28 - 11.7 - 8.3$ $5.4×2.66 + 7.34×5.4$
$3.14×1.25×0.8$ $14.5 - 4.5×3.2$ $1.96×3.7 + 6.3×1.96$
$72×(3.56 + 1.24)$ $1.6×0.25×2.5$ $0.36 + [(3.1 - 3.09)×0.4]$

3.26 + 5.9 + 6.74
=3.26 + 6.74 + 5.9
=10 + 5.9
=15.9
50×0.39×0.4
=50×0.4×0.39
=20×0.39
=7.8
2.8×102
=2.8×(100+2)
=2.8×100 + 2.8×2
=280 + 5.6
=285.6
0.125×73×80
=0.125×80×73
=10×73
=730
28 - 11.7 - 8.3
=28 - (11.7 + 8.3)
=28 - 20
=8
5.4×2.66 + 7.34×5.4
=5.4×(2.66 + 7.34)
=5.4×10
=54
3.14×1.25×0.8
=3.14×(1.25×0.8)
=3.14×1
=3.14
14.5 - 4.5×3.2
=14.5 - 14.4
=0.1
1.96×3.7 + 6.3×1.96
=1.96×(3.7 + 6.3)
=1.96×10
=19.6
72×(3.56 + 1.24)
=72×4.8
=345.6
1.6×0.25×2.5
=(0.4×4)×0.25×2.5
=(0.4×0.25)×(4×2.5)
=0.1×10
=1
0.36 + [(3.1 - 3.09)×0.4]
=0.36 + (0.01×0.4)
=0.36 + 0.004
=0.364